Rollup merge of rust-lang#87507 - jethrogb:jb/sgx-unmoveable-mutex, r…

…=dtolnay SGX mutex is *not* moveable Reverts the erroneous change in rust-lang#85029.
JohnTitor · Jul 28, 2021 · 7987e0f · 7987e0f
2 parents 3a423cc + b518dc7
commit 7987e0f
Show file tree

Hide file tree

Showing 2 changed files with 3 additions and 1 deletion.
diff --git a/library/std/src/sys/sgx/mutex.rs b/library/std/src/sys/sgx/mutex.rs
@@ -8,7 +8,8 @@ pub struct Mutex {
     inner: SpinMutex<WaitVariable<bool>>,
 }
 
-pub type MovableMutex = Mutex;
+// not movable: see UnsafeList implementation
+pub type MovableMutex = Box<Mutex>;
 
 // Implementation according to “Operating Systems: Three Easy Pieces”, chapter 28
 impl Mutex {

diff --git a/library/std/src/sys/sgx/waitqueue/unsafe_list.rs b/library/std/src/sys/sgx/waitqueue/unsafe_list.rs
@@ -23,6 +23,7 @@ impl<T> UnsafeListEntry<T> {
     }
 }
 
+// WARNING: self-referential struct!
 pub struct UnsafeList<T> {
     head_tail: NonNull<UnsafeListEntry<T>>,
     head_tail_entry: Option<UnsafeListEntry<T>>,